|Nearest city||Medora, North Dakota|
|Area||9.9 acres (4.0 ha)|
|Part of||Custer Military Trail Historic Archaeological District (ID08001293)|
|NRHP reference No.||76002271|
|Added to NRHP||November 7, 1976|
|Designated CP||June 5, 2009|
Initial Rock, also known as Name Rock, in the Medora Ranger District of the Little Missouri National Grassland, near Medora, North Dakota, was listed on the National Register of Historic Places (NRHP) in 1976. It was the site of an overnight camp on May 28, 1876 of George Armstrong Custer's men, on their way to the Battle of Little Big Horn, which happened on June 25, 1876. The NRHP listing included one contributing site and one contributing object on 9.9 acres (4.0 ha).
A shelter over the rock has prevented further weathering and vandalism since 1966.
It is one of five sites that are included in Custer Military Trail Historic Archaeological District, which is a large historic district that was listed on the NRHP in 2009. These sites are documented as part of a driving tour through the region.
- "National Register Information System". National Register of Historic Places. National Park Service. July 9, 2010.
- Charles H. Rodgers (April 1975). "National Register of Historic Places Registration: Initial Rock / Name Rock". and accompanying photos